Imaging a Black Hole using only Closure Quantities

In this tutorial, we will create a preliminary reconstruction of the 2017 M87 data on April 6 using closure-only imaging. This tutorial is a general introduction to closure-only imaging in Comrade. For an introduction to simultaneous image and instrument modeling, see Stokes I Simultaneous Image and Instrument Modeling

Introduction to Closure Imaging

The EHT is the highest-resolution telescope ever created. Its resolution is equivalent to roughly tracking a hockey puck on the moon when viewing it from the earth. However, the EHT is also a unique interferometer. For one, the data it produces is incredibly sparse. The array is formed from only eight geographic locations around the planet, each with its unique telescope. Additionally, the EHT observes at a much higher frequency than typical interferometers. As a result, it is often difficult to directly provide calibrated data since the source model can be complicated. This implies there can be large instrumental effects often called gains that can corrupt our signal. One way to deal with this is to fit quantities that are independent of gains. These are often called closure quantities. The types of closure quantities are briefly described in Introduction to the VLBI Imaging Problem.

In this tutorial, we will do closure-only modeling of M87 to produce preliminary images of M87.

To get started, we will load Comrade

using Comrade




using Pyehtim

  Activating project at `~/work/Comrade.jl/Comrade.jl/examples`

For reproducibility we use a stable random number genreator

using StableRNGs
rng = StableRNG(123)

StableRNGs.LehmerRNG(state=0x000000000000000000000000000000f7)

Load the Data

To download the data visit https://doi.org/10.25739/g85n-f134 To load the eht-imaging obsdata object we do:

obs = ehtim.obsdata.load_uvfits(joinpath(dirname(pathof(Comrade)), "..", "examples", "SR1_M87_2017_096_lo_hops_netcal_StokesI.uvfits"))

Python: <ehtim.obsdata.Obsdata object at 0x7fe8b1d6c6d0>

Now we do some minor preprocessing:

• Scan average the data since the data have been preprocessed so that the gain phases are coherent.
• Add 1% systematic noise to deal with calibration issues that cause 1% non-closing errors.

obs = scan_average(obs).add_fractional_noise(0.015)

Python: <ehtim.obsdata.Obsdata object at 0x7fe8adff2a10>

Now, we extract our closure quantities from the EHT data set.

dlcamp, dcphase  = extract_table(obs, LogClosureAmplitudes(;snrcut=3), ClosurePhases(;snrcut=3))

(EHTObservation{Float64,Comrade.EHTLogClosureAmplitudeDatum{Float64}, ...}
  source: M87
  mjd: 57849
  frequency: 2.27070703125e11
  bandwidth: 1.856e9
  stations: [:AA, :AP, :AZ, :JC, :LM, :PV, :SM]
  nsamples: 128
, EHTObservation{Float64,Comrade.EHTClosurePhaseDatum{Float64}, ...}
  source: M87
  mjd: 57849
  frequency: 2.27070703125e11
  bandwidth: 1.856e9
  stations: [:AA, :AP, :AZ, :JC, :LM, :PV, :SM]
  nsamples: 152
)

Build the Model/Posterior

For our model, we will be using an image model that consists of a raster of point sources, convolved with some pulse or kernel to make a ContinuousImage object with it Comrade's. generic image model.

function sky(θ, metadata)
    (;fg, c, σimg) = θ
    (;K, meanpr, grid, cache) = metadata
    # Construct the image model we fix the flux to 0.6 Jy in this case
    cp = meanpr .+ σimg.*c.params
    rast = ((1-fg))*K(to_simplex(CenteredLR(), cp))
    img = IntensityMap(rast, grid)
    m = ContinuousImage(img, cache)
    # Add a large-scale gaussian to deal with the over-resolved mas flux
    g = modify(Gaussian(), Stretch(μas2rad(250.0), μas2rad(250.0)), Renormalize(fg))
    return m + g
end

sky (generic function with 1 method)

Now, let's set up our image model. The EHT's nominal resolution is 20-25 μas. Additionally, the EHT is not very sensitive to a larger field of views; typically, 60-80 μas is enough to describe the compact flux of M87. Given this, we only need to use a small number of pixels to describe our image.

npix = 32
fovxy = μas2rad(150.0)

7.27220521664304e-10

Now, we can feed in the array information to form the cache

grid = imagepixels(fovxy, fovxy, npix, npix)
buffer = IntensityMap(zeros(npix,npix), grid)
cache = create_cache(NFFTAlg(dlcamp), buffer, BSplinePulse{3}())

VLBISkyModels.NUFTCache{VLBISkyModels.ObservedNUFT{NFFTAlg{Float64, AbstractNFFTs.PrecomputeFlags, UInt32}, Matrix{Float64}}, NFFT.NFFTPlan{Float64, 2, 1}, Vector{ComplexF64}, BSplinePulse{3}, KeyedArray{Float64, 2, NamedDimsArray{(:X, :Y), Float64, 2, Matrix{Float64}}, GriddedKeys{(:X, :Y), Tuple{LinRange{Float64, Int64}, LinRange{Float64, Int64}}, ComradeBase.NoHeader, Float64}}}(VLBISkyModels.ObservedNUFT{NFFTAlg{Float64, AbstractNFFTs.PrecomputeFlags, UInt32}, Matrix{Float64}}(NFFTAlg{Float64, AbstractNFFTs.PrecomputeFlags, UInt32}(1, 4, 2.0, :kaiser_bessel, AbstractNFFTs.POLYNOMIAL, true, false, true, 0x00000000), [-4.405690154666661e9 787577.6145833326 … -5.999801315555549e9 -15551.297851562484; -4.523017159111106e9 -1.6838098888888871e6 … 3.059254300444441e9 118294.64453124987]), NFFTPlan with 274 sampling points for an input array of size(32, 32) and an output array of size(274,) with dims 1:2, ComplexF64[0.7014670924816703 - 0.519511453845776im, 0.9999999862106403 - 6.398624051637031e-5im, 0.6947985314160843 - 0.5233374146500747im, 0.9328845732113544 - 0.16336912604935844im, 0.9329421134238738 + 0.16331744240563614im, 0.6948519110447875 + 0.5233083088067162im, 0.7925669922789302 + 0.40478845348863063im, 0.9999999864389528 - 6.519719206334107e-5im, 0.9340555032742773 - 0.1520910238460368im, 0.6896791530194316 - 0.5261728587493705im  …  0.8376666586657548 + 0.1784956664688869im, 0.9196690775195503 + 0.09173305645579018im, 0.9135584686897926 + 0.29199716871629755im, 0.9135610039654034 + 0.2919905620278203im, 0.8899638273254515 + 0.28719490128071723im, 0.9568100109264257 + 0.09814170760184636im, 0.8899622135777404 + 0.287201492222944im, 0.9925668796456906 + 0.0027765725149323534im, 0.8376650833595861 - 0.17848899851834446im, 0.9999999999247222 + 7.335331210317892e-6im], BSplinePulse{3}(), [0.0 0.0 … 0.0 0.0; 0.0 0.0 … 0.0 0.0; … ; 0.0 0.0 … 0.0 0.0; 0.0 0.0 … 0.0 0.0])

Now we need to specify our image prior. For this work we will use a Gaussian Markov Random field prior

using VLBIImagePriors, Distributions, DistributionsAD

Since we are using a Gaussian Markov random field prior we need to first specify our mean image. For this work we will use a symmetric Gaussian with a FWHM of 50 μas

fwhmfac = 2*sqrt(2*log(2))
mpr = modify(Gaussian(), Stretch(μas2rad(50.0)./fwhmfac))
imgpr = intensitymap(mpr, grid)

2-dimensional KeyedArray(NamedDimsArray(...)) with keys:
↓   X ∈ 32-element LinRange{Float64,...}
→   Y ∈ 32-element LinRange{Float64,...}
And data, 32×32 NamedDimsArray(::Matrix{Float64}, (:X, :Y)):
                 (-3.52247e-10)  …  (3.29522e-10)  (3.52247e-10)
 (-3.52247e-10)     6.37537e-8        1.32434e-7     6.37537e-8
 (-3.29522e-10)     1.32434e-7        2.751e-7       1.32434e-7
 (-3.06796e-10)     2.62014e-7        5.44273e-7     2.62014e-7
 (-2.84071e-10)     4.93724e-7        1.0256e-6      4.93724e-7
 (-2.61345e-10)     8.86092e-7   …    1.84065e-6     8.86092e-7
 (-2.38619e-10)     1.51463e-6        3.14629e-6     1.51463e-6
    ⋮                            ⋱    ⋮            
  (2.15894e-10)     2.46586e-6        5.12225e-6     2.46586e-6
  (2.38619e-10)     1.51463e-6        3.14629e-6     1.51463e-6
  (2.61345e-10)     8.86092e-7   …    1.84065e-6     8.86092e-7
  (2.84071e-10)     4.93724e-7        1.0256e-6      4.93724e-7
  (3.06796e-10)     2.62014e-7        5.44273e-7     2.62014e-7
  (3.29522e-10)     1.32434e-7        2.751e-7       1.32434e-7
  (3.52247e-10)     6.37537e-8        1.32434e-7     6.37537e-8

Now since we are actually modeling our image on the simplex we need to ensure that our mean image has unit flux

imgpr ./= flux(imgpr)

meanpr = to_real(CenteredLR(), Comrade.baseimage(imgpr))
metadata = (;meanpr,K=CenterImage(imgpr), grid, cache)

(meanpr = [-7.55422122563378 -6.823167558636962 … -6.823167558636962 -7.55422122563378; -6.823167558636962 -6.092113891640146 … -6.092113891640146 -6.823167558636962; … ; -6.823167558636962 -6.092113891640146 … -6.092113891640146 -6.823167558636962; -7.55422122563378 -6.823167558636962 … -6.823167558636962 -7.55422122563378], K = VLBIImagePriors.CenterImage{Matrix{Float64}, Tuple{Int64, Int64}}([0.9944957386363635 -0.0053267045454545746 … 0.005326704545454565 0.005504261363636378; -0.0053267045454545746 0.9948393969941348 … 0.005160603005865086 0.005326704545454551; … ; 0.005326704545454565 0.005160603005865086 … 0.9948393969941348 -0.005326704545454546; 0.005504261363636378 0.005326704545454551 … -0.005326704545454546 0.9944957386363636], (32, 32)), grid = GriddedKeys{(:X, :Y)}
	X: LinRange{Float64}(-3.5224744018114725e-10, 3.5224744018114725e-10, 32)
	Y: LinRange{Float64}(-3.5224744018114725e-10, 3.5224744018114725e-10, 32)
, cache = VLBISkyModels.NUFTCache{VLBISkyModels.ObservedNUFT{NFFTAlg{Float64, AbstractNFFTs.PrecomputeFlags, UInt32}, Matrix{Float64}}, NFFT.NFFTPlan{Float64, 2, 1}, Vector{ComplexF64}, BSplinePulse{3}, KeyedArray{Float64, 2, NamedDimsArray{(:X, :Y), Float64, 2, Matrix{Float64}}, GriddedKeys{(:X, :Y), Tuple{LinRange{Float64, Int64}, LinRange{Float64, Int64}}, ComradeBase.NoHeader, Float64}}}(VLBISkyModels.ObservedNUFT{NFFTAlg{Float64, AbstractNFFTs.PrecomputeFlags, UInt32}, Matrix{Float64}}(NFFTAlg{Float64, AbstractNFFTs.PrecomputeFlags, UInt32}(1, 4, 2.0, :kaiser_bessel, AbstractNFFTs.POLYNOMIAL, true, false, true, 0x00000000), [-4.405690154666661e9 787577.6145833326 … -5.999801315555549e9 -15551.297851562484; -4.523017159111106e9 -1.6838098888888871e6 … 3.059254300444441e9 118294.64453124987]), NFFTPlan with 274 sampling points for an input array of size(32, 32) and an output array of size(274,) with dims 1:2, ComplexF64[0.7014670924816703 - 0.519511453845776im, 0.9999999862106403 - 6.398624051637031e-5im, 0.6947985314160843 - 0.5233374146500747im, 0.9328845732113544 - 0.16336912604935844im, 0.9329421134238738 + 0.16331744240563614im, 0.6948519110447875 + 0.5233083088067162im, 0.7925669922789302 + 0.40478845348863063im, 0.9999999864389528 - 6.519719206334107e-5im, 0.9340555032742773 - 0.1520910238460368im, 0.6896791530194316 - 0.5261728587493705im  …  0.8376666586657548 + 0.1784956664688869im, 0.9196690775195503 + 0.09173305645579018im, 0.9135584686897926 + 0.29199716871629755im, 0.9135610039654034 + 0.2919905620278203im, 0.8899638273254515 + 0.28719490128071723im, 0.9568100109264257 + 0.09814170760184636im, 0.8899622135777404 + 0.287201492222944im, 0.9925668796456906 + 0.0027765725149323534im, 0.8376650833595861 - 0.17848899851834446im, 0.9999999999247222 + 7.335331210317892e-6im], BSplinePulse{3}(), [0.0 0.0 … 0.0 0.0; 0.0 0.0 … 0.0 0.0; … ; 0.0 0.0 … 0.0 0.0; 0.0 0.0 … 0.0 0.0]))

In addition we want a reasonable guess for what the resolution of our image should be. For radio astronomy this is given by roughly the longest baseline in the image. To put this into pixel space we then divide by the pixel size.

beam = beamsize(dlcamp)
rat = (beam/(step(grid.X)))

5.326336637737519

To make the Gaussian Markov random field efficient we first precompute a bunch of quantities that allow us to scale things linearly with the number of image pixels. This drastically improves the usual N^3 scaling you get from usual Gaussian Processes.

crcache = MarkovRandomFieldCache(meanpr)

VLBIImagePriors.MarkovRandomFieldCache{SparseArrays.SparseMatrixCSC{Float64, Int64}, LinearAlgebra.Diagonal{Float64, Vector{Float64}}, Matrix{Float64}}(sparse([1, 2, 32, 33, 993, 1, 2, 3, 34, 994  …  31, 991, 1022, 1023, 1024, 32, 992, 993, 1023, 1024], [1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 16, 16, 16, 16, 16, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 19, 19, 19, 19, 19, 20, 20, 20, 20, 20, 21, 21, 21, 21, 21, 22, 22, 22, 22, 22, 23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 25, 25, 25, 25, 25, 26, 26, 26, 26, 26, 27, 27, 27, 27, 27, 28, 28, 28, 28, 28, 29, 29, 29, 29, 29, 30, 30, 30, 30, 30, 31, 31, 31, 31, 31, 32, 32, 32, 32, 32, 33, 33, 33, 33, 33, 34, 34, 34, 34, 34, 35, 35, 35, 35, 35, 36, 36, 36, 36, 36, 37, 37, 37, 37, 37, 38, 38, 38, 38, 38, 39, 39, 39, 39, 39, 40, 40, 40, 40, 40, 41, 41, 41, 41, 41, 42, 42, 42, 42, 42, 43, 43, 43, 43, 43, 44, 44, 44, 44, 44, 45, 45, 45, 45, 45, 46, 46, 46, 46, 46, 47, 47, 47, 47, 47, 48, 48, 48, 48, 48, 49, 49, 49, 49, 49, 50, 50, 50, 50, 50, 51, 51, 51, 51, 51, 52, 52, 52, 52, 52, 53, 53, 53, 53, 53, 54, 54, 54, 54, 54, 55, 55, 55, 55, 55, 56, 56, 56, 56, 56, 57, 57, 57, 57, 57, 58, 58, 58, 58, 58, 59, 59, 59, 59, 59, 60, 60, 60, 60, 60, 61, 61, 61, 61, 61, 62, 62, 62, 62, 62, 63, 63, 63, 63, 63, 64, 64, 64, 64, 64, 65, 65, 65, 65, 65, 66, 66, 66, 66, 66, 67, 67, 67, 67, 67, 68, 68, 68, 68, 68, 69, 69, 69, 69, 69, 70, 70, 70, 70, 70, 71, 71, 71, 71, 71, 72, 72, 72, 72, 72, 73, 73, 73, 73, 73, 74, 74, 74, 74, 74, 75, 75, 75, 75, 75, 76, 76, 76, 76, 76, 77, 77, 77, 77, 77, 78, 78, 78, 78, 78, 79, 79, 79, 79, 79, 80, 80, 80, 80, 80, 81, 81, 81, 81, 81, 82, 82, 82, 82, 82, 83, 83, 83, 83, 83, 84, 84, 84, 84, 84, 85, 85, 85, 85, 85, 86, 86, 86, 86, 86, 87, 87, 87, 87, 87, 88, 88, 88, 88, 88, 89, 89, 89, 89, 89, 90, 90, 90, 90, 90, 91, 91, 91, 91, 91, 92, 92, 92, 92, 92, 93, 93, 93, 93, 93, 94, 94, 94, 94, 94, 95, 95, 95, 95, 95, 96, 96, 96, 96, 96, 97, 97, 97, 97, 97, 98, 98, 98, 98, 98, 99, 99, 99, 99, 99, 100, 100, 100, 100, 100, 101, 101, 101, 101, 101, 102, 102, 102, 102, 102, 103, 103, 103, 103, 103, 104, 104, 104, 104, 104, 105, 105, 105, 105, 105, 106, 106, 106, 106, 106, 107, 107, 107, 107, 107, 108, 108, 108, 108, 108, 109, 109, 109, 109, 109, 110, 110, 110, 110, 110, 111, 111, 111, 111, 111, 112, 112, 112, 112, 112, 113, 113, 113, 113, 113, 114, 114, 114, 114, 114, 115, 115, 115, 115, 115, 116, 116, 116, 116, 116, 117, 117, 117, 117, 117, 118, 118, 118, 118, 118, 119, 119, 119, 119, 119, 120, 120, 120, 120, 120, 121, 121, 121, 121, 121, 122, 122, 122, 122, 122, 123, 123, 123, 123, 123, 124, 124, 124, 124, 124, 125, 125, 125, 125, 125, 126, 126, 126, 126, 126, 127, 127, 127, 127, 127, 128, 128, 128, 128, 128, 129, 129, 129, 129, 129, 130, 130, 130, 130, 130, 131, 131, 131, 131, 131, 132, 132, 132, 132, 132, 133, 133, 133, 133, 133, 134, 134, 134, 134, 134, 135, 135, 135, 135, 135, 136, 136, 136, 136, 136, 137, 137, 137, 137, 137, 138, 138, 138, 138, 138, 139, 139, 139, 139, 139, 140, 140, 140, 140, 140, 141, 141, 141, 141, 141, 142, 142, 142, 142, 142, 143, 143, 143, 143, 143, 144, 144, 144, 144, 144, 145, 145, 145, 145, 145, 146, 146, 146, 146, 146, 147, 147, 147, 147, 147, 148, 148, 148, 148, 148, 149, 149, 149, 149, 149, 150, 150, 150, 150, 150, 151, 151, 151, 151, 151, 152, 152, 152, 152, 152, 153, 153, 153, 153, 153, 154, 154, 154, 154, 154, 155, 155, 155, 155, 155, 156, 156, 156, 156, 156, 157, 157, 157, 157, 157, 158, 158, 158, 158, 158, 159, 159, 159, 159, 159, 160, 160, 160, 160, 160, 161, 161, 161, 161, 161, 162, 162, 162, 162, 162, 163, 163, 163, 163, 163, 164, 164, 164, 164, 164, 165, 165, 165, 165, 165, 166, 166, 166, 166, 166, 167, 167, 167, 167, 167, 168, 168, 168, 168, 168, 169, 169, 169, 169, 169, 170, 170, 170, 170, 170, 171, 171, 171, 171, 171, 172, 172, 172, 172, 172, 173, 173, 173, 173, 173, 174, 174, 174, 174, 174, 175, 175, 175, 175, 175, 176, 176, 176, 176, 176, 177, 177, 177, 177, 177, 178, 178, 178, 178, 178, 179, 179, 179, 179, 179, 180, 180, 180, 180, 180, 181, 181, 181, 181, 181, 182, 182, 182, 182, 182, 183, 183, 183, 183, 183, 184, 184, 184, 184, 184, 185, 185, 185, 185, 185, 186, 186, 186, 186, 186, 187, 187, 187, 187, 187, 188, 188, 188, 188, 188, 189, 189, 189, 189, 189, 190, 190, 190, 190, 190, 191, 191, 191, 191, 191, 192, 192, 192, 192, 192, 193, 193, 193, 193, 193, 194, 194, 194, 194, 194, 195, 195, 195, 195, 195, 196, 196, 196, 196, 196, 197, 197, 197, 197, 197, 198, 198, 198, 198, 198, 199, 199, 199, 199, 199, 200, 200, 200, 200, 200, 201, 201, 201, 201, 201, 202, 202, 202, 202, 202, 203, 203, 203, 203, 203, 204, 204, 204, 204, 204, 205, 205, 205, 205, 205, 206, 206, 206, 206, 206, 207, 207, 207, 207, 207, 208, 208, 208, 208, 208, 209, 209, 209, 209, 209, 210, 210, 210, 210, 210, 211, 211, 211, 211, 211, 212, 212, 212, 212, 212, 213, 213, 213, 213, 213, 214, 214, 214, 214, 214, 215, 215, 215, 215, 215, 216, 216, 216, 216, 216, 217, 217, 217, 217, 217, 218, 218, 218, 218, 218, 219, 219, 219, 219, 219, 220, 220, 220, 220, 220, 221, 221, 221, 221, 221, 222, 222, 222, 222, 222, 223, 223, 223, 223, 223, 224, 224, 224, 224, 224, 225, 225, 225, 225, 225, 226, 226, 226, 226, 226, 227, 227, 227, 227, 227, 228, 228, 228, 228, 228, 229, 229, 229, 229, 229, 230, 230, 230, 230, 230, 231, 231, 231, 231, 231, 232, 232, 232, 232, 232, 233, 233, 233, 233, 233, 234, 234, 234, 234, 234, 235, 235, 235, 235, 235, 236, 236, 236, 236, 236, 237, 237, 237, 237, 237, 238, 238, 238, 238, 238, 239, 239, 239, 239, 239, 240, 240, 240, 240, 240, 241, 241, 241, 241, 241, 242, 242, 242, 242, 242, 243, 243, 243, 243, 243, 244, 244, 244, 244, 244, 245, 245, 245, 245, 245, 246, 246, 246, 246, 246, 247, 247, 247, 247, 247, 248, 248, 248, 248, 248, 249, 249, 249, 249, 249, 250, 250, 250, 250, 250, 251, 251, 251, 251, 251, 252, 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892, 892, 892, 892, 893, 893, 893, 893, 893, 894, 894, 894, 894, 894, 895, 895, 895, 895, 895, 896, 896, 896, 896, 896, 897, 897, 897, 897, 897, 898, 898, 898, 898, 898, 899, 899, 899, 899, 899, 900, 900, 900, 900, 900, 901, 901, 901, 901, 901, 902, 902, 902, 902, 902, 903, 903, 903, 903, 903, 904, 904, 904, 904, 904, 905, 905, 905, 905, 905, 906, 906, 906, 906, 906, 907, 907, 907, 907, 907, 908, 908, 908, 908, 908, 909, 909, 909, 909, 909, 910, 910, 910, 910, 910, 911, 911, 911, 911, 911, 912, 912, 912, 912, 912, 913, 913, 913, 913, 913, 914, 914, 914, 914, 914, 915, 915, 915, 915, 915, 916, 916, 916, 916, 916, 917, 917, 917, 917, 917, 918, 918, 918, 918, 918, 919, 919, 919, 919, 919, 920, 920, 920, 920, 920, 921, 921, 921, 921, 921, 922, 922, 922, 922, 922, 923, 923, 923, 923, 923, 924, 924, 924, 924, 924, 925, 925, 925, 925, 925, 926, 926, 926, 926, 926, 927, 927, 927, 927, 927, 928, 928, 928, 928, 928, 929, 929, 929, 929, 929, 930, 930, 930, 930, 930, 931, 931, 931, 931, 931, 932, 932, 932, 932, 932, 933, 933, 933, 933, 933, 934, 934, 934, 934, 934, 935, 935, 935, 935, 935, 936, 936, 936, 936, 936, 937, 937, 937, 937, 937, 938, 938, 938, 938, 938, 939, 939, 939, 939, 939, 940, 940, 940, 940, 940, 941, 941, 941, 941, 941, 942, 942, 942, 942, 942, 943, 943, 943, 943, 943, 944, 944, 944, 944, 944, 945, 945, 945, 945, 945, 946, 946, 946, 946, 946, 947, 947, 947, 947, 947, 948, 948, 948, 948, 948, 949, 949, 949, 949, 949, 950, 950, 950, 950, 950, 951, 951, 951, 951, 951, 952, 952, 952, 952, 952, 953, 953, 953, 953, 953, 954, 954, 954, 954, 954, 955, 955, 955, 955, 955, 956, 956, 956, 956, 956, 957, 957, 957, 957, 957, 958, 958, 958, 958, 958, 959, 959, 959, 959, 959, 960, 960, 960, 960, 960, 961, 961, 961, 961, 961, 962, 962, 962, 962, 962, 963, 963, 963, 963, 963, 964, 964, 964, 964, 964, 965, 965, 965, 965, 965, 966, 966, 966, 966, 966, 967, 967, 967, 967, 967, 968, 968, 968, 968, 968, 969, 969, 969, 969, 969, 970, 970, 970, 970, 970, 971, 971, 971, 971, 971, 972, 972, 972, 972, 972, 973, 973, 973, 973, 973, 974, 974, 974, 974, 974, 975, 975, 975, 975, 975, 976, 976, 976, 976, 976, 977, 977, 977, 977, 977, 978, 978, 978, 978, 978, 979, 979, 979, 979, 979, 980, 980, 980, 980, 980, 981, 981, 981, 981, 981, 982, 982, 982, 982, 982, 983, 983, 983, 983, 983, 984, 984, 984, 984, 984, 985, 985, 985, 985, 985, 986, 986, 986, 986, 986, 987, 987, 987, 987, 987, 988, 988, 988, 988, 988, 989, 989, 989, 989, 989, 990, 990, 990, 990, 990, 991, 991, 991, 991, 991, 992, 992, 992, 992, 992, 993, 993, 993, 993, 993, 994, 994, 994, 994, 994, 995, 995, 995, 995, 995, 996, 996, 996, 996, 996, 997, 997, 997, 997, 997, 998, 998, 998, 998, 998, 999, 999, 999, 999, 999, 1000, 1000, 1000, 1000, 1000, 1001, 1001, 1001, 1001, 1001, 1002, 1002, 1002, 1002, 1002, 1003, 1003, 1003, 1003, 1003, 1004, 1004, 1004, 1004, 1004, 1005, 1005, 1005, 1005, 1005, 1006, 1006, 1006, 1006, 1006, 1007, 1007, 1007, 1007, 1007, 1008, 1008, 1008, 1008, 1008, 1009, 1009, 1009, 1009, 1009, 1010, 1010, 1010, 1010, 1010, 1011, 1011, 1011, 1011, 1011, 1012, 1012, 1012, 1012, 1012, 1013, 1013, 1013, 1013, 1013, 1014, 1014, 1014, 1014, 1014, 1015, 1015, 1015, 1015, 1015, 1016, 1016, 1016, 1016, 1016, 1017, 1017, 1017, 1017, 1017, 1018, 1018, 1018, 1018, 1018, 1019, 1019, 1019, 1019, 1019, 1020, 1020, 1020, 1020, 1020, 1021, 1021, 1021, 1021, 1021, 1022, 1022, 1022, 1022, 1022, 1023, 1023, 1023, 1023, 1023, 1024, 1024, 1024, 1024, 1024], [4.0, -1.0, -1.0, -1.0, -1.0, -1.0, 4.0, -1.0, -1.0, -1.0  …  -1.0, -1.0, -1.0, 4.0, -1.0, -1.0, -1.0, -1.0, -1.0, 4.0], 1024, 1024), [1.0 0.0 … 0.0 0.0; 0.0 1.0 … 0.0 0.0; … ; 0.0 0.0 … 1.0 0.0; 0.0 0.0 … 0.0 1.0], [0.0 0.03842943919353914 … 0.15224093497742697 0.03842943919353936; 0.03842943919353914 0.07685887838707828 … 0.1906703741709661 0.0768588783870785; … ; 0.15224093497742697 0.1906703741709661 … 0.30448186995485393 0.19067037417096633; 0.03842943919353914 0.07685887838707828 … 0.1906703741709661 0.0768588783870785])

One of the benefits of the Bayesian approach is that we can fit for the hyperparameters of our prior/regularizers unlike traditional RML appraoches. To construct this heirarchical prior we will first make a map that takes in our regularizer hyperparameters and returns the image prior given those hyperparameters.

fmap = let crcache=crcache
    x->GaussMarkovRandomField(x, 1.0, crcache)
end

#1 (generic function with 1 method)

Now we can finally form our image prior. For this we use a heirarchical prior where the correlation length is given by a inverse gamma prior to prevent overfitting. Gaussian Markov random fields are extremly flexible models. To prevent overfitting it is common to use priors that penalize complexity. Therefore, we want to use priors that enforce similarity to our mean image, and prefer smoothness.

cprior = HierarchicalPrior(fmap, InverseGamma(1.0, -log(0.01*rat)))

prior = NamedDist(c = cprior, σimg = truncated(Normal(0.0, 0.1); lower = 0.0), fg=Uniform(0.0, 1.0))

lklhd = RadioLikelihood(sky, dlcamp, dcphase;
                        skymeta = metadata)
post = Posterior(lklhd, prior)

Posterior{RadioLikelihood{Comrade.ModelMetadata{typeof(Main.sky), NamedTuple{(:meanpr, :K, :grid, :cache), Tuple{Matrix{Float64}, VLBIImagePriors.CenterImage{Matrix{Float64}, Tuple{Int64, Int64}}, GriddedKeys{(:X, :Y), Tuple{LinRange{Float64, Int64}, LinRange{Float64, Int64}}, ComradeBase.NoHeader, Float64}, VLBISkyModels.NUFTCache{VLBISkyModels.ObservedNUFT{NFFTAlg{Float64, AbstractNFFTs.PrecomputeFlags, UInt32}, Matrix{Float64}}, NFFT.NFFTPlan{Float64, 2, 1}, Vector{ComplexF64}, BSplinePulse{3}, KeyedArray{Float64, 2, NamedDimsArray{(:X, :Y), Float64, 2, Matrix{Float64}}, GriddedKeys{(:X, :Y), Tuple{LinRange{Float64, Int64}, LinRange{Float64, Int64}}, ComradeBase.NoHeader, Float64}}}}}}, Nothing, Tuple{Comrade.EHTObservation{Float64, Comrade.EHTLogClosureAmplitudeDatum{Float64}, StructArrays.StructVector{Comrade.EHTLogClosureAmplitudeDatum{Float64}, NamedTuple{(:measurement, :error, :U1, :V1, :U2, :V2, :U3, :V3, :U4, :V4, :T, :F, :quadrangle), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{NTuple{4, Symbol}}}}, Int64}, Comrade.ClosureConfig{Comrade.EHTObservation{Float64, Comrade.EHTVisibilityDatum{Float64}, StructArrays.StructVector{Comrade.EHTVisibilityDatum{Float64}, NamedTuple{(:measurement, :error, :U, :V, :T, :F, :baseline), Tuple{Vector{ComplexF64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}}}, Int64}, Comrade.EHTArrayConfiguration{Float64, TypedTables.Table{NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Symbol, Vararg{Float64, 8}}}, 1, NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Vector{Symbol}, Vararg{Vector{Float64}, 8}}}}, TypedTables.Table{NamedTuple{(:start, :stop), Tuple{Float64, Float64}}, 1, NamedTuple{(:start, :stop), Tuple{Vector{Float64}, Vector{Float64}}}}, StructArrays.StructVector{Comrade.ArrayBaselineDatum, NamedTuple{(:U, :V, :T, :F, :baseline, :error, :elevation, :parallactic), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}, Vector{Float64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}}}, Int64}}, Int64}, SparseArrays.SparseMatrixCSC{Float64, Int64}}, Int64}, Comrade.EHTObservation{Float64, Comrade.EHTClosurePhaseDatum{Float64}, StructArrays.StructVector{Comrade.EHTClosurePhaseDatum{Float64}, NamedTuple{(:measurement, :error, :U1, :V1, :U2, :V2, :U3, :V3, :T, :F, :triangle), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol, Symbol}}}}, Int64}, Comrade.ClosureConfig{Comrade.EHTObservation{Float64, Comrade.EHTVisibilityDatum{Float64}, StructArrays.StructVector{Comrade.EHTVisibilityDatum{Float64}, NamedTuple{(:measurement, :error, :U, :V, :T, :F, :baseline), Tuple{Vector{ComplexF64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}}}, Int64}, Comrade.EHTArrayConfiguration{Float64, TypedTables.Table{NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Symbol, Vararg{Float64, 8}}}, 1, NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Vector{Symbol}, Vararg{Vector{Float64}, 8}}}}, TypedTables.Table{NamedTuple{(:start, :stop), Tuple{Float64, Float64}}, 1, NamedTuple{(:start, :stop), Tuple{Vector{Float64}, Vector{Float64}}}}, StructArrays.StructVector{Comrade.ArrayBaselineDatum, NamedTuple{(:U, :V, :T, :F, :baseline, :error, :elevation, :parallactic), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}, Vector{Float64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}}}, Int64}}, Int64}, SparseArrays.SparseMatrixCSC{Float64, Int64}}, Int64}}, Tuple{Comrade.ConditionedLikelihood{Comrade.var"#34#35"{Float64, Base.Fix2{typeof(logclosure_amplitudes), Comrade.ClosureConfig{Comrade.EHTObservation{Float64, Comrade.EHTVisibilityDatum{Float64}, StructArrays.StructVector{Comrade.EHTVisibilityDatum{Float64}, NamedTuple{(:measurement, :error, :U, :V, :T, :F, :baseline), Tuple{Vector{ComplexF64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}}}, Int64}, Comrade.EHTArrayConfiguration{Float64, TypedTables.Table{NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Symbol, Vararg{Float64, 8}}}, 1, NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Vector{Symbol}, Vararg{Vector{Float64}, 8}}}}, TypedTables.Table{NamedTuple{(:start, :stop), Tuple{Float64, Float64}}, 1, NamedTuple{(:start, :stop), Tuple{Vector{Float64}, Vector{Float64}}}}, StructArrays.StructVector{Comrade.ArrayBaselineDatum, NamedTuple{(:U, :V, :T, :F, :baseline, :error, :elevation, :parallactic), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}, Vector{Float64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}}}, Int64}}, Int64}, SparseArrays.SparseMatrixCSC{Float64, Int64}}}, VLBILikelihoods.CholeskyFactor{Float64, SparseArrays.SparseMatrixCSC{Float64, Int64}, SparseArrays.CHOLMOD.Factor{Float64}}}, Vector{Float64}}, Comrade.ConditionedLikelihood{Comrade.var"#36#37"{Float64, Base.Fix2{typeof(closure_phases), Comrade.ClosureConfig{Comrade.EHTObservation{Float64, Comrade.EHTVisibilityDatum{Float64}, StructArrays.StructVector{Comrade.EHTVisibilityDatum{Float64}, NamedTuple{(:measurement, :error, :U, :V, :T, :F, :baseline), Tuple{Vector{ComplexF64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}}}, Int64}, Comrade.EHTArrayConfiguration{Float64, TypedTables.Table{NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Symbol, Vararg{Float64, 8}}}, 1, NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Vector{Symbol}, Vararg{Vector{Float64}, 8}}}}, TypedTables.Table{NamedTuple{(:start, :stop), Tuple{Float64, Float64}}, 1, NamedTuple{(:start, :stop), Tuple{Vector{Float64}, Vector{Float64}}}}, StructArrays.StructVector{Comrade.ArrayBaselineDatum, NamedTuple{(:U, :V, :T, :F, :baseline, :error, :elevation, :parallactic), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}, Vector{Float64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}}}, Int64}}, Int64}, SparseArrays.SparseMatrixCSC{Float64, Int64}}}, VLBILikelihoods.CholeskyFactor{Float64, SparseArrays.SparseMatrixCSC{Float64, Int64}, SparseArrays.CHOLMOD.Factor{Float64}}}, Vector{Float64}}}, Comrade.ClosureConfig{Comrade.EHTObservation{Float64, Comrade.EHTVisibilityDatum{Float64}, StructArrays.StructVector{Comrade.EHTVisibilityDatum{Float64}, NamedTuple{(:measurement, :error, :U, :V, :T, :F, :baseline), Tuple{Vector{ComplexF64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}}}, Int64}, Comrade.EHTArrayConfiguration{Float64, TypedTables.Table{NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Symbol, Vararg{Float64, 8}}}, 1, NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Vector{Symbol}, Vararg{Vector{Float64}, 8}}}}, TypedTables.Table{NamedTuple{(:start, :stop), Tuple{Float64, Float64}}, 1, NamedTuple{(:start, :stop), Tuple{Vector{Float64}, Vector{Float64}}}}, StructArrays.StructVector{Comrade.ArrayBaselineDatum, NamedTuple{(:U, :V, :T, :F, :baseline, :error, :elevation, :parallactic), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}, Vector{Float64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}}}, Int64}}, Int64}, SparseArrays.SparseMatrixCSC{Float64, Int64}}, NamedTuple{(:U, :V, :T, :F), NTuple{4, Vector{Float64}}}}, VLBIImagePriors.NamedDist{(:c, :σimg, :fg), Tuple{VLBIImagePriors.HierarchicalPrior{Main.var"#1#2"{VLBIImagePriors.MarkovRandomFieldCache{SparseArrays.SparseMatrixCSC{Float64, Int64}, LinearAlgebra.Diagonal{Float64, Vector{Float64}}, Matrix{Float64}}}, Distributions.InverseGamma{Float64}}, Distributions.Truncated{Distributions.Normal{Float64}, Distributions.Continuous, Float64, Float64, Nothing}, Distributions.Uniform{Float64}}}}(RadioLikelihood
	Number of data products: 2
, VLBIImagePriors.NamedDist{(:c, :σimg, :fg), Tuple{VLBIImagePriors.HierarchicalPrior{Main.var"#1#2"{VLBIImagePriors.MarkovRandomFieldCache{SparseArrays.SparseMatrixCSC{Float64, Int64}, LinearAlgebra.Diagonal{Float64, Vector{Float64}}, Matrix{Float64}}}, Distributions.InverseGamma{Float64}}, Distributions.Truncated{Distributions.Normal{Float64}, Distributions.Continuous, Float64, Float64, Nothing}, Distributions.Uniform{Float64}}}(
dists: (VLBIImagePriors.HierarchicalPrior{Main.var"#1#2"{VLBIImagePriors.MarkovRandomFieldCache{SparseArrays.SparseMatrixCSC{Float64, Int64}, LinearAlgebra.Diagonal{Float64, Vector{Float64}}, Matrix{Float64}}}, Distributions.InverseGamma{Float64}}(
priormap: #1
hyperprior: Distributions.InverseGamma{Float64}(
invd: Distributions.Gamma{Float64}(α=1.0, θ=0.3410052124381751)
θ: 2.932506494109095
)

)
, Truncated(Distributions.Normal{Float64}(μ=0.0, σ=0.1); lower=0.0), Distributions.Uniform{Float64}(a=0.0, b=1.0))
)
)

Reconstructing the Image

To sample from this posterior, it is convenient to first move from our constrained parameter space to an unconstrained one (i.e., the support of the transformed posterior is (-∞, ∞)). This is done using the asflat function.

tpost = asflat(post)

Comrade.TransformedPosterior{Posterior{RadioLikelihood{Comrade.ModelMetadata{typeof(Main.sky), NamedTuple{(:meanpr, :K, :grid, :cache), Tuple{Matrix{Float64}, VLBIImagePriors.CenterImage{Matrix{Float64}, Tuple{Int64, Int64}}, GriddedKeys{(:X, :Y), Tuple{LinRange{Float64, Int64}, LinRange{Float64, Int64}}, ComradeBase.NoHeader, Float64}, VLBISkyModels.NUFTCache{VLBISkyModels.ObservedNUFT{NFFTAlg{Float64, AbstractNFFTs.PrecomputeFlags, UInt32}, Matrix{Float64}}, NFFT.NFFTPlan{Float64, 2, 1}, Vector{ComplexF64}, BSplinePulse{3}, KeyedArray{Float64, 2, NamedDimsArray{(:X, :Y), Float64, 2, Matrix{Float64}}, GriddedKeys{(:X, :Y), Tuple{LinRange{Float64, Int64}, LinRange{Float64, Int64}}, ComradeBase.NoHeader, Float64}}}}}}, Nothing, Tuple{Comrade.EHTObservation{Float64, Comrade.EHTLogClosureAmplitudeDatum{Float64}, StructArrays.StructVector{Comrade.EHTLogClosureAmplitudeDatum{Float64}, NamedTuple{(:measurement, :error, :U1, :V1, :U2, :V2, :U3, :V3, :U4, :V4, :T, :F, :quadrangle), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{NTuple{4, Symbol}}}}, Int64}, Comrade.ClosureConfig{Comrade.EHTObservation{Float64, Comrade.EHTVisibilityDatum{Float64}, StructArrays.StructVector{Comrade.EHTVisibilityDatum{Float64}, NamedTuple{(:measurement, :error, :U, :V, :T, :F, :baseline), Tuple{Vector{ComplexF64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}}}, Int64}, Comrade.EHTArrayConfiguration{Float64, TypedTables.Table{NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Symbol, Vararg{Float64, 8}}}, 1, NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Vector{Symbol}, Vararg{Vector{Float64}, 8}}}}, TypedTables.Table{NamedTuple{(:start, :stop), Tuple{Float64, Float64}}, 1, NamedTuple{(:start, :stop), Tuple{Vector{Float64}, Vector{Float64}}}}, StructArrays.StructVector{Comrade.ArrayBaselineDatum, NamedTuple{(:U, :V, :T, :F, :baseline, :error, :elevation, :parallactic), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}, Vector{Float64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}}}, Int64}}, Int64}, SparseArrays.SparseMatrixCSC{Float64, Int64}}, Int64}, Comrade.EHTObservation{Float64, Comrade.EHTClosurePhaseDatum{Float64}, StructArrays.StructVector{Comrade.EHTClosurePhaseDatum{Float64}, NamedTuple{(:measurement, :error, :U1, :V1, :U2, :V2, :U3, :V3, :T, :F, :triangle), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol, Symbol}}}}, Int64}, Comrade.ClosureConfig{Comrade.EHTObservation{Float64, Comrade.EHTVisibilityDatum{Float64}, StructArrays.StructVector{Comrade.EHTVisibilityDatum{Float64}, NamedTuple{(:measurement, :error, :U, :V, :T, :F, :baseline), Tuple{Vector{ComplexF64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}}}, Int64}, Comrade.EHTArrayConfiguration{Float64, TypedTables.Table{NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Symbol, Vararg{Float64, 8}}}, 1, NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Vector{Symbol}, Vararg{Vector{Float64}, 8}}}}, TypedTables.Table{NamedTuple{(:start, :stop), Tuple{Float64, Float64}}, 1, NamedTuple{(:start, :stop), Tuple{Vector{Float64}, Vector{Float64}}}}, StructArrays.StructVector{Comrade.ArrayBaselineDatum, NamedTuple{(:U, :V, :T, :F, :baseline, :error, :elevation, :parallactic), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}, Vector{Float64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}}}, Int64}}, Int64}, SparseArrays.SparseMatrixCSC{Float64, Int64}}, Int64}}, Tuple{Comrade.ConditionedLikelihood{Comrade.var"#34#35"{Float64, Base.Fix2{typeof(logclosure_amplitudes), Comrade.ClosureConfig{Comrade.EHTObservation{Float64, Comrade.EHTVisibilityDatum{Float64}, StructArrays.StructVector{Comrade.EHTVisibilityDatum{Float64}, NamedTuple{(:measurement, :error, :U, :V, :T, :F, :baseline), Tuple{Vector{ComplexF64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}}}, Int64}, Comrade.EHTArrayConfiguration{Float64, TypedTables.Table{NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Symbol, Vararg{Float64, 8}}}, 1, NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Vector{Symbol}, Vararg{Vector{Float64}, 8}}}}, TypedTables.Table{NamedTuple{(:start, :stop), Tuple{Float64, Float64}}, 1, NamedTuple{(:start, :stop), Tuple{Vector{Float64}, Vector{Float64}}}}, StructArrays.StructVector{Comrade.ArrayBaselineDatum, NamedTuple{(:U, :V, :T, :F, :baseline, :error, :elevation, :parallactic), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}, Vector{Float64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}}}, Int64}}, Int64}, SparseArrays.SparseMatrixCSC{Float64, Int64}}}, VLBILikelihoods.CholeskyFactor{Float64, SparseArrays.SparseMatrixCSC{Float64, Int64}, SparseArrays.CHOLMOD.Factor{Float64}}}, Vector{Float64}}, Comrade.ConditionedLikelihood{Comrade.var"#36#37"{Float64, Base.Fix2{typeof(closure_phases), Comrade.ClosureConfig{Comrade.EHTObservation{Float64, Comrade.EHTVisibilityDatum{Float64}, StructArrays.StructVector{Comrade.EHTVisibilityDatum{Float64}, NamedTuple{(:measurement, :error, :U, :V, :T, :F, :baseline), Tuple{Vector{ComplexF64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}}}, Int64}, Comrade.EHTArrayConfiguration{Float64, TypedTables.Table{NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Symbol, Vararg{Float64, 8}}}, 1, NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Vector{Symbol}, Vararg{Vector{Float64}, 8}}}}, TypedTables.Table{NamedTuple{(:start, :stop), Tuple{Float64, Float64}}, 1, NamedTuple{(:start, :stop), Tuple{Vector{Float64}, Vector{Float64}}}}, StructArrays.StructVector{Comrade.ArrayBaselineDatum, NamedTuple{(:U, :V, :T, :F, :baseline, :error, :elevation, :parallactic), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}, Vector{Float64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}}}, Int64}}, Int64}, SparseArrays.SparseMatrixCSC{Float64, Int64}}}, VLBILikelihoods.CholeskyFactor{Float64, SparseArrays.SparseMatrixCSC{Float64, Int64}, SparseArrays.CHOLMOD.Factor{Float64}}}, Vector{Float64}}}, Comrade.ClosureConfig{Comrade.EHTObservation{Float64, Comrade.EHTVisibilityDatum{Float64}, StructArrays.StructVector{Comrade.EHTVisibilityDatum{Float64}, NamedTuple{(:measurement, :error, :U, :V, :T, :F, :baseline), Tuple{Vector{ComplexF64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}}}, Int64}, Comrade.EHTArrayConfiguration{Float64, TypedTables.Table{NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Symbol, Vararg{Float64, 8}}}, 1, NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Vector{Symbol}, Vararg{Vector{Float64}, 8}}}}, TypedTables.Table{NamedTuple{(:start, :stop), Tuple{Float64, Float64}}, 1, NamedTuple{(:start, :stop), Tuple{Vector{Float64}, Vector{Float64}}}}, StructArrays.StructVector{Comrade.ArrayBaselineDatum, NamedTuple{(:U, :V, :T, :F, :baseline, :error, :elevation, :parallactic), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}, Vector{Float64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}}}, Int64}}, Int64}, SparseArrays.SparseMatrixCSC{Float64, Int64}}, NamedTuple{(:U, :V, :T, :F), NTuple{4, Vector{Float64}}}}, VLBIImagePriors.NamedDist{(:c, :σimg, :fg), Tuple{VLBIImagePriors.HierarchicalPrior{Main.var"#1#2"{VLBIImagePriors.MarkovRandomFieldCache{SparseArrays.SparseMatrixCSC{Float64, Int64}, LinearAlgebra.Diagonal{Float64, Vector{Float64}}, Matrix{Float64}}}, Distributions.InverseGamma{Float64}}, Distributions.Truncated{Distributions.Normal{Float64}, Distributions.Continuous, Float64, Float64, Nothing}, Distributions.Uniform{Float64}}}}, TransformVariables.TransformTuple{NamedTuple{(:c, :σimg, :fg), Tuple{TransformVariables.TransformTuple{NamedTuple{(:params, :hyperparams), Tuple{TransformVariables.ArrayTransformation{TransformVariables.Identity, 2}, TransformVariables.ShiftedExp{true, Float64}}}}, TransformVariables.ShiftedExp{true, Float64}, TransformVariables.ScaledShiftedLogistic{Float64}}}}}(Posterior{RadioLikelihood{Comrade.ModelMetadata{typeof(Main.sky), NamedTuple{(:meanpr, :K, :grid, :cache), Tuple{Matrix{Float64}, VLBIImagePriors.CenterImage{Matrix{Float64}, Tuple{Int64, Int64}}, GriddedKeys{(:X, :Y), Tuple{LinRange{Float64, Int64}, LinRange{Float64, Int64}}, ComradeBase.NoHeader, Float64}, VLBISkyModels.NUFTCache{VLBISkyModels.ObservedNUFT{NFFTAlg{Float64, AbstractNFFTs.PrecomputeFlags, UInt32}, Matrix{Float64}}, NFFT.NFFTPlan{Float64, 2, 1}, Vector{ComplexF64}, BSplinePulse{3}, KeyedArray{Float64, 2, NamedDimsArray{(:X, :Y), Float64, 2, Matrix{Float64}}, GriddedKeys{(:X, :Y), Tuple{LinRange{Float64, Int64}, LinRange{Float64, Int64}}, ComradeBase.NoHeader, Float64}}}}}}, Nothing, Tuple{Comrade.EHTObservation{Float64, Comrade.EHTLogClosureAmplitudeDatum{Float64}, StructArrays.StructVector{Comrade.EHTLogClosureAmplitudeDatum{Float64}, NamedTuple{(:measurement, :error, :U1, :V1, :U2, :V2, :U3, :V3, :U4, :V4, :T, :F, :quadrangle), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{NTuple{4, Symbol}}}}, Int64}, Comrade.ClosureConfig{Comrade.EHTObservation{Float64, Comrade.EHTVisibilityDatum{Float64}, StructArrays.StructVector{Comrade.EHTVisibilityDatum{Float64}, NamedTuple{(:measurement, :error, :U, :V, :T, :F, :baseline), Tuple{Vector{ComplexF64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}}}, Int64}, Comrade.EHTArrayConfiguration{Float64, TypedTables.Table{NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Symbol, Vararg{Float64, 8}}}, 1, NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Vector{Symbol}, Vararg{Vector{Float64}, 8}}}}, TypedTables.Table{NamedTuple{(:start, :stop), Tuple{Float64, Float64}}, 1, NamedTuple{(:start, :stop), Tuple{Vector{Float64}, Vector{Float64}}}}, StructArrays.StructVector{Comrade.ArrayBaselineDatum, NamedTuple{(:U, :V, :T, :F, :baseline, :error, :elevation, :parallactic), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}, Vector{Float64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}}}, Int64}}, Int64}, SparseArrays.SparseMatrixCSC{Float64, Int64}}, Int64}, Comrade.EHTObservation{Float64, Comrade.EHTClosurePhaseDatum{Float64}, StructArrays.StructVector{Comrade.EHTClosurePhaseDatum{Float64}, NamedTuple{(:measurement, :error, :U1, :V1, :U2, :V2, :U3, :V3, :T, :F, :triangle), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol, Symbol}}}}, Int64}, Comrade.ClosureConfig{Comrade.EHTObservation{Float64, Comrade.EHTVisibilityDatum{Float64}, StructArrays.StructVector{Comrade.EHTVisibilityDatum{Float64}, NamedTuple{(:measurement, :error, :U, :V, :T, :F, :baseline), Tuple{Vector{ComplexF64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}}}, Int64}, Comrade.EHTArrayConfiguration{Float64, TypedTables.Table{NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Symbol, Vararg{Float64, 8}}}, 1, NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Vector{Symbol}, Vararg{Vector{Float64}, 8}}}}, TypedTables.Table{NamedTuple{(:start, :stop), Tuple{Float64, Float64}}, 1, NamedTuple{(:start, :stop), Tuple{Vector{Float64}, Vector{Float64}}}}, StructArrays.StructVector{Comrade.ArrayBaselineDatum, NamedTuple{(:U, :V, :T, :F, :baseline, :error, :elevation, :parallactic), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}, Vector{Float64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}}}, Int64}}, Int64}, SparseArrays.SparseMatrixCSC{Float64, Int64}}, Int64}}, Tuple{Comrade.ConditionedLikelihood{Comrade.var"#34#35"{Float64, Base.Fix2{typeof(logclosure_amplitudes), Comrade.ClosureConfig{Comrade.EHTObservation{Float64, Comrade.EHTVisibilityDatum{Float64}, StructArrays.StructVector{Comrade.EHTVisibilityDatum{Float64}, NamedTuple{(:measurement, :error, :U, :V, :T, :F, :baseline), Tuple{Vector{ComplexF64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}}}, Int64}, Comrade.EHTArrayConfiguration{Float64, TypedTables.Table{NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Symbol, Vararg{Float64, 8}}}, 1, NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Vector{Symbol}, Vararg{Vector{Float64}, 8}}}}, TypedTables.Table{NamedTuple{(:start, :stop), Tuple{Float64, Float64}}, 1, NamedTuple{(:start, :stop), Tuple{Vector{Float64}, Vector{Float64}}}}, StructArrays.StructVector{Comrade.ArrayBaselineDatum, NamedTuple{(:U, :V, :T, :F, :baseline, :error, :elevation, :parallactic), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}, Vector{Float64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}}}, Int64}}, Int64}, SparseArrays.SparseMatrixCSC{Float64, Int64}}}, VLBILikelihoods.CholeskyFactor{Float64, SparseArrays.SparseMatrixCSC{Float64, Int64}, SparseArrays.CHOLMOD.Factor{Float64}}}, Vector{Float64}}, Comrade.ConditionedLikelihood{Comrade.var"#36#37"{Float64, Base.Fix2{typeof(closure_phases), Comrade.ClosureConfig{Comrade.EHTObservation{Float64, Comrade.EHTVisibilityDatum{Float64}, StructArrays.StructVector{Comrade.EHTVisibilityDatum{Float64}, NamedTuple{(:measurement, :error, :U, :V, :T, :F, :baseline), Tuple{Vector{ComplexF64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}}}, Int64}, Comrade.EHTArrayConfiguration{Float64, TypedTables.Table{NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Symbol, Vararg{Float64, 8}}}, 1, NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Vector{Symbol}, Vararg{Vector{Float64}, 8}}}}, TypedTables.Table{NamedTuple{(:start, :stop), Tuple{Float64, Float64}}, 1, NamedTuple{(:start, :stop), Tuple{Vector{Float64}, Vector{Float64}}}}, StructArrays.StructVector{Comrade.ArrayBaselineDatum, NamedTuple{(:U, :V, :T, :F, :baseline, :error, :elevation, :parallactic), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}, Vector{Float64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}}}, Int64}}, Int64}, SparseArrays.SparseMatrixCSC{Float64, Int64}}}, VLBILikelihoods.CholeskyFactor{Float64, SparseArrays.SparseMatrixCSC{Float64, Int64}, SparseArrays.CHOLMOD.Factor{Float64}}}, Vector{Float64}}}, Comrade.ClosureConfig{Comrade.EHTObservation{Float64, Comrade.EHTVisibilityDatum{Float64}, StructArrays.StructVector{Comrade.EHTVisibilityDatum{Float64}, NamedTuple{(:measurement, :error, :U, :V, :T, :F, :baseline), Tuple{Vector{ComplexF64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}}}, Int64}, Comrade.EHTArrayConfiguration{Float64, TypedTables.Table{NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Symbol, Vararg{Float64, 8}}}, 1, NamedTuple{(:sites, :X, :Y, :Z, :SEFD1, :SEFD2, :fr_parallactic, :fr_elevation, :fr_offset), Tuple{Vector{Symbol}, Vararg{Vector{Float64}, 8}}}}, TypedTables.Table{NamedTuple{(:start, :stop), Tuple{Float64, Float64}}, 1, NamedTuple{(:start, :stop), Tuple{Vector{Float64}, Vector{Float64}}}}, StructArrays.StructVector{Comrade.ArrayBaselineDatum, NamedTuple{(:U, :V, :T, :F, :baseline, :error, :elevation, :parallactic), Tuple{Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Float64}, Vector{Tuple{Symbol, Symbol}}, Vector{Float64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}, StructArrays.StructVector{Tuple{Float64, Float64}, Tuple{Vector{Float64}, Vector{Float64}}, Int64}}}, Int64}}, Int64}, SparseArrays.SparseMatrixCSC{Float64, Int64}}, NamedTuple{(:U, :V, :T, :F), NTuple{4, Vector{Float64}}}}, VLBIImagePriors.NamedDist{(:c, :σimg, :fg), Tuple{VLBIImagePriors.HierarchicalPrior{Main.var"#1#2"{VLBIImagePriors.MarkovRandomFieldCache{SparseArrays.SparseMatrixCSC{Float64, Int64}, LinearAlgebra.Diagonal{Float64, Vector{Float64}}, Matrix{Float64}}}, Distributions.InverseGamma{Float64}}, Distributions.Truncated{Distributions.Normal{Float64}, Distributions.Continuous, Float64, Float64, Nothing}, Distributions.Uniform{Float64}}}}(RadioLikelihood
	Number of data products: 2
, VLBIImagePriors.NamedDist{(:c, :σimg, :fg), Tuple{VLBIImagePriors.HierarchicalPrior{Main.var"#1#2"{VLBIImagePriors.MarkovRandomFieldCache{SparseArrays.SparseMatrixCSC{Float64, Int64}, LinearAlgebra.Diagonal{Float64, Vector{Float64}}, Matrix{Float64}}}, Distributions.InverseGamma{Float64}}, Distributions.Truncated{Distributions.Normal{Float64}, Distributions.Continuous, Float64, Float64, Nothing}, Distributions.Uniform{Float64}}}(
dists: (VLBIImagePriors.HierarchicalPrior{Main.var"#1#2"{VLBIImagePriors.MarkovRandomFieldCache{SparseArrays.SparseMatrixCSC{Float64, Int64}, LinearAlgebra.Diagonal{Float64, Vector{Float64}}, Matrix{Float64}}}, Distributions.InverseGamma{Float64}}(
priormap: #1
hyperprior: Distributions.InverseGamma{Float64}(
invd: Distributions.Gamma{Float64}(α=1.0, θ=0.3410052124381751)
θ: 2.932506494109095
)

)
, Truncated(Distributions.Normal{Float64}(μ=0.0, σ=0.1); lower=0.0), Distributions.Uniform{Float64}(a=0.0, b=1.0))
)
), TransformVariables.TransformTuple{NamedTuple{(:c, :σimg, :fg), Tuple{TransformVariables.TransformTuple{NamedTuple{(:params, :hyperparams), Tuple{TransformVariables.ArrayTransformation{TransformVariables.Identity, 2}, TransformVariables.ShiftedExp{true, Float64}}}}, TransformVariables.ShiftedExp{true, Float64}, TransformVariables.ScaledShiftedLogistic{Float64}}}}((c = TransformVariables.TransformTuple{NamedTuple{(:params, :hyperparams), Tuple{TransformVariables.ArrayTransformation{TransformVariables.Identity, 2}, TransformVariables.ShiftedExp{true, Float64}}}}((params = TransformVariables.ArrayTransformation{TransformVariables.Identity, 2}(asℝ, (32, 32)), hyperparams = as(Real, 0.0, ∞)), 1025), σimg = as(Real, 0.0, ∞), fg = as(Real, 0.0, 1.0)), 1027))

We can now also find the dimension of our posterior or the number of parameters we will sample.

ndim = dimension(tpost)

1027

Now we optimize using LBFGS

using ComradeOptimization
using OptimizationOptimJL
using Zygote
f = OptimizationFunction(tpost, Optimization.AutoZygote())
prob = Optimization.OptimizationProblem(f, prior_sample(rng, tpost), nothing)
sol = solve(prob, LBFGS(); maxiters=5_00);

Before we analyze our solution we first need to transform back to parameter space.

xopt = transform(tpost, sol)

(c = (params = [-0.7540899656319622 -0.7766682440013806 … -0.7071854085061485 -0.7259413626472166; -0.760526674856007 -0.7802434483682645 … -0.7182192539232248 -0.7357493944621932; … ; -0.7337365131588275 -0.7595175962103428 … -0.6845238237594602 -0.7041350663626422; -0.7445430684518516 -0.7718026773915733 … -0.6961306205740406 -0.7175424129210984], hyperparams = 14.351962592319412), σimg = 0.7477102858287898, fg = 0.03828798506047278)

First we will evaluate our fit by plotting the residuals

using Plots
residual(skymodel(post, xopt), dlcamp, ylabel="Log Closure Amplitude Res.")

and now closure phases

residual(skymodel(post, xopt), dcphase, ylabel="|Closure Phase Res.|")

Now let's plot the MAP estimate.

import WGLMakie as CM
img = intensitymap(skymodel(post, xopt), μas2rad(150.0), μas2rad(150.0), 100, 100)
CM.image(img, axis=(xreversed=true, aspect=1, title="MAP Image"), colormap=:afmhot, figure=(;resolution=(400, 400),))

To sample from the posterior we will use HMC and more specifically the NUTS algorithm. For information about NUTS see Michael Betancourt's notes.

using ComradeAHMC
using Zygote
metric = DiagEuclideanMetric(ndim)
chain, stats = sample(post, AHMC(;metric, autodiff=Val(:Zygote)), 700; nadapts=500, init_params=xopt)

(NamedTuple{(:c, :σimg, :fg), Tuple{NamedTuple{(:params, :hyperparams), Tuple{Matrix{Float64}, Float64}}, Float64, Float64}}[(c = (params = [-0.7801563021382856 -0.7699454771593781 … -0.7646700568670578 -0.7431777711748011; -0.7638206844510964 -0.6758200127394224 … -0.7381447200506825 -0.7122511315915738; … ; -0.7398726904115961 -0.6336277656933996 … -0.6649140766708566 -0.606768533681792; -0.7376958261869434 -0.7733051705976599 … -0.7256443512598093 -0.7810731230115506], hyperparams = 12.88940406887815), σimg = 0.755204193453544, fg = 0.03663142371455198), (c = (params = [-0.9673985162268538 0.1882206680361706 … -0.965444220460669 -0.8250701272750102; -1.0774534160008886 -1.6858095149889027 … -0.4374046989452421 -0.8660571131096461; … ; -0.32127735383418066 -0.9576718264686893 … -0.8249569261256773 -0.5052356840848377; -0.9714535837897713 -0.26894244287231384 … -0.5256307546768072 -0.35987161535269924], hyperparams = 18.20530971864882), σimg = 0.7605169796987112, fg = 0.009281685309249554), (c = (params = [-1.2160558440332805 -0.3360172659536977 … -0.6496414269068305 -0.8353047851513621; -0.7470002194203325 -2.3352407149428362 … -0.7046009727380973 -0.6924455494234185; … ; -0.5505948903014706 -0.5041811093264772 … -0.6556324603143592 -0.37390815241652114; -1.1479559078105956 -0.49073577077980424 … -0.6769666942544309 -0.7341148058197793], hyperparams = 15.191677140199518), σimg = 0.737387079683538, fg = 0.01521038174876358), (c = (params = [-1.1163918590709898 -2.2593166612177797 … -0.7301021449531357 -0.8328990281787148; -1.7014181171158755 -0.2998013924608839 … -0.5687976293776947 -1.1051911116883497; … ; -0.6980708979696939 -0.27508838026458016 … -0.822815997680123 -1.1922132345857945; -0.5370925065737812 -0.9623816848544905 … -1.031479587166985 -1.162935338162288], hyperparams = 22.86618837866518), σimg = 0.5673327647916386, fg = 0.06896843332473088), (c = (params = [-1.1076715018936758 -2.260922055245493 … -0.7348097716220001 -0.8179469909041351; -1.723176316106067 -0.3114423129403887 … -0.5408446880700657 -1.1475169312768305; … ; -0.6943401393286043 -0.24559360210770506 … -0.8121233560231986 -1.1945333184780937; -0.5950802320407457 -0.9797885856065766 … -1.0450714529023746 -1.1510733893258511], hyperparams = 22.15930130239018), σimg = 0.5695307683751665, fg = 0.06793642814748233), (c = (params = [0.628773456104666 -0.4957789776044566 … -0.3016916292353817 0.3756841258502633; -0.2906056601906862 -0.19508525171810445 … -0.5503597583885419 -0.5243558844022603; … ; -0.03267606021141939 -0.40730377618551195 … -0.12202921173046344 0.47137535149293086; 0.504917412493753 -0.12911901111474558 … -0.8350876364922208 0.18441920966527992], hyperparams = 22.19713581370247), σimg = 0.7887298570739301, fg = 0.09325285406020015), (c = (params = [-1.8193243064099265 -1.4301471091337474 … -0.03567221623438438 -0.9745784495535835; -1.2270754280732556 -2.183977600598575 … -0.22176322373481527 -1.1566464949686015; … ; 0.05615985935870439 -0.23803897348688863 … 0.2724249730748976 0.07006412370456333; -1.322697304860272 -0.7152744249705065 … 0.5962089035918146 -0.029891594163734207], hyperparams = 21.21271372513046), σimg = 0.5707930870140767, fg = 0.05838990029076038), (c = (params = [-1.0009314528834607 -1.6430288197575016 … -0.6171978560353379 -0.5457483899214624; -2.0743467275382304 -2.039625184682363 … -1.4638000229413064 -2.017101656174665; … ; -0.19457367344596274 -0.049024212277657034 … -0.809836840093595 -0.19198939736926543; -0.28168485986923913 -0.8491245597771019 … -0.7587478519373241 -0.21464407087178217], hyperparams = 14.251093212490902), σimg = 0.6078573789663805, fg = 0.16419211928239608), (c = (params = [-1.0009314528834607 -1.6430288197575016 … -0.6171978560353379 -0.5457483899214624; -2.0743467275382304 -2.039625184682363 … -1.4638000229413064 -2.017101656174665; … ; -0.19457367344596274 -0.049024212277657034 … -0.809836840093595 -0.19198939736926543; -0.28168485986923913 -0.8491245597771019 … -0.7587478519373241 -0.21464407087178217], hyperparams = 14.251093212490902), σimg = 0.6078573789663805, fg = 0.16419211928239608), (c = (params = [-0.6999843739214807 -1.7597677473802436 … -1.0951444070515635 -0.740542588950226; -2.0699550913185694 -2.4309256695012977 … -0.8541348334410652 -1.6837236799647821; … ; -0.4592560245695549 -0.3780453555802486 … -0.32245721000736155 0.13141143037201555; -0.8758467797046464 -0.5894622427846697 … -0.6736678962241167 0.49389384370440165], hyperparams = 12.64417475463791), σimg = 0.5859233547761684, fg = 0.06691507388394556)  …  (c = (params = [0.7594106448945056 0.9215684839721094 … 0.07045706662167303 1.048855649728453; 1.3384616961909914 0.42478647026987776 … -0.3350703021643046 0.5762240271386228; … ; -1.1305922397514006 -0.8230515812109653 … -1.2371940978075013 -0.813397053223162; -0.09032570294053358 0.10234318362867802 … 0.2363781656716745 -0.004059430000591779], hyperparams = 27.194602096453764), σimg = 0.7277657497773781, fg = 0.03766993966657185), (c = (params = [-0.18780705645074144 -0.6463043965486233 … -0.577150228531387 -0.45909453892314267; 0.0266154560860503 0.1796730770335889 … 0.43376860250834687 0.18229236010744385; … ; 0.09978478187896318 -0.03325004275100662 … -0.4346316157071126 0.2785957951428289; 0.21490305182559089 -1.0197283797578158 … -1.320781352371533 -0.3383323665113006], hyperparams = 8.27436851166033), σimg = 0.7872036152948124, fg = 0.03164033505549882), (c = (params = [-0.5030291924584027 0.4565085462160896 … -0.31362635525966864 -0.4591079516664295; -0.046659325912079955 -0.06603967977318537 … -0.43585802143561575 -0.683477733555738; … ; -0.7960584212030207 -0.0926179920117031 … -0.7358454690278265 -0.8342734617288106; -0.9201894540847939 0.2384700981209101 … 0.4505928688936867 -1.045140427047672], hyperparams = 26.321642100064423), σimg = 0.745847767003162, fg = 0.06490554066536841), (c = (params = [-0.43147153057271564 0.06541718357925104 … -0.23776047136169487 0.07076970061715876; -0.42091888999797045 0.7908243601989461 … 0.07164879562380369 0.4699459564847562; … ; -0.5774354118305511 -0.4095426728959509 … -0.12718739006563748 -1.4360138363139936; 0.02758292814437574 -0.2770293957739512 … -0.7283826357211834 -0.13666224032371252], hyperparams = 14.345923620029687), σimg = 0.689177212239355, fg = 0.027383470770664914), (c = (params = [0.173145297524867 0.1050797400419328 … -0.38827144919468254 -0.29316558223812667; 0.7682372084264081 -0.9093953176453018 … -0.5787702311183676 -0.7006662214667759; … ; -0.2858736482296831 -0.8249892700467218 … -1.0869173859663992 0.10740242640276465; -0.5286182161316384 -0.20472362172681688 … 0.08516455073742962 -0.24873576627273097], hyperparams = 10.438350683168917), σimg = 0.6773688854435184, fg = 0.04856896647111293), (c = (params = [-1.0246652532603773 -0.8186499381752551 … 0.22329814213471916 -0.004751365294398629; -1.416325581373978 0.14880763537017544 … 0.29317675449474506 0.22209830779626927; … ; -0.7958713798358547 0.1904897795214941 … 0.344728930388018 -0.4500474060177659; -0.11736547004574319 -0.10589618421563723 … -0.20926205895664426 0.22155783763641876], hyperparams = 13.285107958499069), σimg = 0.7784666266716462, fg = 0.013524724755276258), (c = (params = [-0.4380189043009877 -0.9126868064313239 … 0.0016237669592769326 -0.46647667238891694; 0.9498340548099797 -0.7473147992324329 … -0.4675727429028419 -0.5261401600853162; … ; -0.1605609731284856 0.0891235855271697 … -1.088214229558211 -0.05143254529095613; -0.4005042993697527 0.021099367676763094 … 0.7451802502994442 -0.5065300715341768], hyperparams = 8.831390978777051), σimg = 0.7085757423008208, fg = 0.009849369906322701), (c = (params = [-0.24671360325751268 0.7233741986101021 … -1.8800952210403206 -0.8699828127351903; -0.37707887254503203 -0.11443992788279865 … -1.6296159440970392 -1.8649195787627717; … ; -0.6266913055266808 -0.11350940221056813 … -0.7144693198899132 -0.7965143143801658; -0.8283795015344169 0.03492046450616564 … -1.244077663326859 -1.4142725982161497], hyperparams = 28.083991683400367), σimg = 0.7951847083929229, fg = 0.1174734976473763), (c = (params = [-0.27267433415946163 0.5477377220181253 … -1.9022594184851278 -1.0531739861918232; -1.5118223294272382 -0.5508045845264299 … -1.8529870720418968 -0.997474104340592; … ; -0.3624415058781127 0.02865462388609152 … -1.2091909456330996 -1.368418696432887; -0.6239198290331536 0.1295651173747564 … -1.2306351974109986 -1.08872671896778], hyperparams = 20.98745604868374), σimg = 0.7540195292732267, fg = 0.046533591432488), (c = (params = [-0.8729385053484052 -0.8843729751260997 … -0.17513675700869935 -0.5412366086066276; 0.5292859360045709 0.10363202497813911 … -0.03461332037623269 0.06111929613788178; … ; -0.14751885658403607 0.24246108689667312 … -0.05608217623945817 0.20783724343701587; 0.015976347633336125 -0.0668233114380231 … -0.09499639022994928 -0.05967099559822431], hyperparams = 7.420475863856856), σimg = 0.6917633662185828, fg = 0.13731467675097442)], NamedTuple{(:n_steps, :is_accept, :acceptance_rate, :log_density, :hamiltonian_energy, :hamiltonian_energy_error, :max_hamiltonian_energy_error, :tree_depth, :numerical_error, :step_size, :nom_step_size, :is_adapt), Tuple{Int64, Bool, Float64, Float64, Float64, Float64, Float64, Int64, Bool, Float64, Float64, Bool}}[(n_steps = 1023, is_accept = 1, acceptance_rate = 0.9999691462884172, log_density = -200.44183204535935, hamiltonian_energy = 697.2816123068736, hamiltonian_energy_error = 3.9097079593375383e-5, max_hamiltonian_energy_error = 5.289461728352762e-5, tree_depth = 10, numerical_error = 0, step_size = 0.0001, nom_step_size = 0.0001, is_adapt = 1), (n_steps = 1023, is_accept = 1, acceptance_rate = 0.9913423986220014, log_density = -567.4264823658065, hamiltonian_energy = 665.3039763521093, hamiltonian_energy_error = 0.007794510730263937, max_hamiltonian_energy_error = 0.024141682749245774, tree_depth = 10, numerical_error = 0, step_size = 0.0015753687264163407, nom_step_size = 0.0015753687264163407, is_adapt = 1), (n_steps = 1023, is_accept = 1, acceptance_rate = 0.9910807656555923, log_density = -624.8768098419022, hamiltonian_energy = 1130.4059551367664, hamiltonian_energy_error = -0.03296341364011823, max_hamiltonian_energy_error = -0.04598611150549914, tree_depth = 9, numerical_error = 0, step_size = 0.0031836629881122724, nom_step_size = 0.0031836629881122724, is_adapt = 1), (n_steps = 255, is_accept = 1, acceptance_rate = 0.9744111813795774, log_density = -652.1650274867242, hamiltonian_energy = 1098.7249262332418, hamiltonian_energy_error = 0.05018106835018443, max_hamiltonian_energy_error = -0.09198416915137386, tree_depth = 8, numerical_error = 0, step_size = 0.00703994998761287, nom_step_size = 0.00703994998761287, is_adapt = 1), (n_steps = 15, is_accept = 1, acceptance_rate = 0.37928339789430227, log_density = -653.8711478688685, hamiltonian_energy = 1150.692214190713, hamiltonian_energy_error = -0.24484738399587513, max_hamiltonian_energy_error = 1563.9796334130392, tree_depth = 3, numerical_error = 1, step_size = 0.015390097185862097, nom_step_size = 0.015390097185862097, is_adapt = 1), (n_steps = 1023, is_accept = 1, acceptance_rate = 0.9933225386825083, log_density = -718.8010987566721, hamiltonian_energy = 1185.1025512402298, hamiltonian_energy_error = 0.001926630756315717, max_hamiltonian_energy_error = -0.03359902556962879, tree_depth = 10, numerical_error = 0, step_size = 0.005739508054520464, nom_step_size = 0.005739508054520464, is_adapt = 1), (n_steps = 467, is_accept = 1, acceptance_rate = 0.6370731046296416, log_density = -716.2936605206991, hamiltonian_energy = 1241.9577409544559, hamiltonian_energy_error = 0.4473701323072419, max_hamiltonian_energy_error = 2150.78803267588, tree_depth = 8, numerical_error = 1, step_size = 0.012673806200372702, nom_step_size = 0.012673806200372702, is_adapt = 1), (n_steps = 255, is_accept = 1, acceptance_rate = 0.9730155333858215, log_density = -719.3896299035503, hamiltonian_energy = 1239.3532833699455, hamiltonian_energy_error = 0.020348460976492788, max_hamiltonian_energy_error = -0.17647710466962963, tree_depth = 8, numerical_error = 0, step_size = 0.009301338873014327, nom_step_size = 0.009301338873014327, is_adapt = 1), (n_steps = 3, is_accept = 1, acceptance_rate = 1.2763646146495142e-9, log_density = -719.3896299035503, hamiltonian_energy = 1248.568144436161, hamiltonian_energy_error = 0.0, max_hamiltonian_energy_error = 20877.490246711473, tree_depth = 1, numerical_error = 1, step_size = 0.019154881126672296, nom_step_size = 0.019154881126672296, is_adapt = 1), (n_steps = 1023, is_accept = 1, acceptance_rate = 0.9996482009474683, log_density = -719.1580894600423, hamiltonian_energy = 1241.530826881551, hamiltonian_energy_error = -0.0010109243166880333, max_hamiltonian_energy_error = -0.006239624587578874, tree_depth = 10, numerical_error = 0, step_size = 0.0018192329405128935, nom_step_size = 0.0018192329405128935, is_adapt = 1)  …  (n_steps = 127, is_accept = 1, acceptance_rate = 0.9715285270293846, log_density = -678.3022212519325, hamiltonian_energy = 1212.4712944614535, hamiltonian_energy_error = 0.05551806740163556, max_hamiltonian_energy_error = -0.4336946906084904, tree_depth = 7, numerical_error = 0, step_size = 0.024273943944002077, nom_step_size = 0.024273943944002077, is_adapt = 0), (n_steps = 127, is_accept = 1, acceptance_rate = 0.9130078755459812, log_density = -688.9760368022345, hamiltonian_energy = 1194.610725640526, hamiltonian_energy_error = -0.037458568745705634, max_hamiltonian_energy_error = -0.5966203418561236, tree_depth = 7, numerical_error = 0, step_size = 0.024273943944002077, nom_step_size = 0.024273943944002077, is_adapt = 0), (n_steps = 127, is_accept = 1, acceptance_rate = 0.9992296965585418, log_density = -690.9443486825775, hamiltonian_energy = 1153.0530668972401, hamiltonian_energy_error = -0.31651707660535067, max_hamiltonian_energy_error = -0.4697748056451019, tree_depth = 7, numerical_error = 0, step_size = 0.024273943944002077, nom_step_size = 0.024273943944002077, is_adapt = 0), (n_steps = 127, is_accept = 1, acceptance_rate = 0.708143778035359, log_density = -670.44824829128, hamiltonian_energy = 1177.5717423872707, hamiltonian_energy_error = 0.43438206170822014, max_hamiltonian_energy_error = 0.7472920572311068, tree_depth = 7, numerical_error = 0, step_size = 0.024273943944002077, nom_step_size = 0.024273943944002077, is_adapt = 0), (n_steps = 127, is_accept = 1, acceptance_rate = 0.933259130903577, log_density = -665.6250995695691, hamiltonian_energy = 1201.7482880557695, hamiltonian_energy_error = -0.1047204604046783, max_hamiltonian_energy_error = -0.41559771369520604, tree_depth = 7, numerical_error = 0, step_size = 0.024273943944002077, nom_step_size = 0.024273943944002077, is_adapt = 0), (n_steps = 127, is_accept = 1, acceptance_rate = 0.9835911205721924, log_density = -658.4398383175513, hamiltonian_energy = 1159.1430109820064, hamiltonian_energy_error = 0.21390897377636975, max_hamiltonian_energy_error = -0.3213113587337375, tree_depth = 7, numerical_error = 0, step_size = 0.024273943944002077, nom_step_size = 0.024273943944002077, is_adapt = 0), (n_steps = 127, is_accept = 1, acceptance_rate = 0.5624562781556628, log_density = -675.3062467682875, hamiltonian_energy = 1169.8777843903874, hamiltonian_energy_error = 0.5684105172831551, max_hamiltonian_energy_error = 1.606950228233245, tree_depth = 7, numerical_error = 0, step_size = 0.024273943944002077, nom_step_size = 0.024273943944002077, is_adapt = 0), (n_steps = 127, is_accept = 1, acceptance_rate = 0.8759328517981475, log_density = -717.6857361153881, hamiltonian_energy = 1204.188583517704, hamiltonian_energy_error = -0.8998814373223922, max_hamiltonian_energy_error = -0.9571658494830899, tree_depth = 7, numerical_error = 0, step_size = 0.024273943944002077, nom_step_size = 0.024273943944002077, is_adapt = 0), (n_steps = 127, is_accept = 1, acceptance_rate = 0.7218840210052427, log_density = -728.9315484600739, hamiltonian_energy = 1236.2997172232435, hamiltonian_energy_error = 0.331769910483672, max_hamiltonian_energy_error = 0.8813922108811312, tree_depth = 7, numerical_error = 0, step_size = 0.024273943944002077, nom_step_size = 0.024273943944002077, is_adapt = 0), (n_steps = 127, is_accept = 1, acceptance_rate = 0.6715801002084671, log_density = -705.0778963658115, hamiltonian_energy = 1237.119192495054, hamiltonian_energy_error = 0.6427827979130143, max_hamiltonian_energy_error = 1.1326440143584477, tree_depth = 7, numerical_error = 0, step_size = 0.024273943944002077, nom_step_size = 0.024273943944002077, is_adapt = 0)])

Now that we have our posterior, we can assess which parts of the image are strongly inferred by the data. This is rather unique to Comrade where more traditional imaging algorithms like CLEAN and RML are inherently unable to assess uncertainty in their reconstructions.

To explore our posterior let's first create images from a bunch of draws from the posterior

msamples = skymodel.(Ref(post), chain[501:2:end]);

The mean image is then given by

using StatsBase
imgs = intensitymap.(msamples, μas2rad(150.0), μas2rad(150.0), 128, 128)
mimg = mean(imgs)
simg = std(imgs)
fig = CM.Figure(;resolution=(400, 400));
CM.image(fig[1,1], mimg,
                   axis=(xreversed=true, aspect=1, title="Mean Image"),
                   colormap=:afmhot)
CM.image(fig[1,2], simg./(max.(mimg, 1e-5)),
                   axis=(xreversed=true, aspect=1, title="1/SNR",), colorrange=(0.0, 2.0),
                   colormap=:afmhot)
CM.image(fig[2,1], imgs[1],
                   axis=(xreversed=true, aspect=1,title="Draw 1"),
                   colormap=:afmhot)
CM.image(fig[2,2], imgs[end],
                   axis=(xreversed=true, aspect=1,title="Draw 2"),
                   colormap=:afmhot)
fig

Now let's see whether our residuals look better.

p = plot();
for s in sample(chain[501:end], 10)
    residual!(p, vlbimodel(post, s), dlcamp)
end
ylabel!("Log-Closure Amplitude Res.");
p

p = plot();
for s in sample(chain[501:end], 10)
    residual!(p, vlbimodel(post, s), dcphase)
end
ylabel!("|Closure Phase Res.|");
p

And viola, you have a quick and preliminary image of M87 fitting only closure products. For a publication-level version we would recommend

1. Running the chain longer and multiple times to properly assess things like ESS and R̂ (see Geometric Modeling of EHT Data)
2. Fitting gains. Typically gain amplitudes are good to 10-20% for the EHT not the infinite uncertainty closures implicitly assume
3. Making sure the posterior is unimodal (hint for this example it isn't!). The EHT image posteriors can be pretty complicated, so typically you want to use a sampler that can deal with multi-modal posteriors. Check out the package Pigeons.jl for an in-development package that should easily enable this type of sampling.

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